With the rapid development of the electronic industry and information technology industry, the replacement of electronic products is becoming faster and the product life cycle shorter, so a large number of electronic products are discarded to forming plentiful electronic wastes. There are large amounts of toxic and harmful substances, for example, heavy metals, such as lead, mercury, cadmium and chromium etc. in electronic wastes especially in electronic circuit boards. If these wastes were handled improperly, the ecological environment and human health would be faced with a great threat. Therefore, retrieving metals from the waste electronic circuit boards demands prompt solution.
At present, the methods of retrieving metals from waste printed circuit boards mainly cover pyrometallurgy, hydrometallurgy and physical methods. Conventional pyrometallurgy and hydrometallurgy have developed to maturation and have been used widely, but there are so many problems, such as serious pollution, long process, high cost and more waste acid and waste liquid, that these methods could not satisfy the requirements of today's resource recovery and environmental protection. The physical method is the earliest and most widely used separation and recovery method of electronic wastes, which means the materials are retrieved through gravity separation, magnetic separation, electric separation and flotation-separation based on the differences of the density, particle size, magnetic and conductive properties of the substances in the circuit board. As a physical method, supergravity separation can separate different materials selectively depending on differences of densities and melting points to aim the recovery rapidly under the condition of gravity field. Supergravity separation technology, as a kind of potential separation process, not only could enrich and separate metals fast and efficiently but also have advantages of low labor intensity, good environmental conditions, small equipment, low energy consumption and cost, easy to scale production etc.